Title:
CONSTANT VOLTAGE CIRCUIT
Document Type and Number:
Japanese Patent JPS6089218
Kind Code:
A
Abstract:
PURPOSE:To hold the output voltage with extremely high stability despite the load variance or the temperature drift by applying the reference voltage to the base of the 1st transistor Tr and having an equal emitter current between the 1st and 2nd Trs. CONSTITUTION:The base-emitter voltage of transistors Tr23 and 24 are set at VBEP and VBEN respectively. Thus the output voltage VCC is shown as VCC= VB+VBEP-VBEN, where VB means the reference voltage. Here a current flowing through a load 27 is referred to as IL, and the emitter currents IE1 and IE2 of Tr23 and 24 are equal to each other. Then IE1=IE2=IL/2 is satisfied. Here voltages VBEP and VBEN are equal to the functions of the temperature T and currents IE1 and IE2. Therefore, VBEP(T,IE1)=VBEN(T,IE2) is satisfied regardless of levels of the temperature T and currents IE1 and IE2. Thus VCC=VB is satisfied and the output voltage is decided just by the reference voltage VB.
Inventors:
UYAMA KAZUYUKI
Application Number:
JP19531483A
Publication Date:
May 20, 1985
Filing Date:
October 20, 1983
Export Citation:
Assignee:
TOSHIBA KK
International Classes:
G05F1/56; G05F3/22; (IPC1-7): G05F1/56
Attorney, Agent or Firm:
Noriyuki Noriyuki
Previous Patent: Photo polymerization resin containing a photo polymerization resin composition and this
Next Patent: POWER SUPPLY DEVICE
Next Patent: POWER SUPPLY DEVICE